Gas diode linear register



July 14, 1959 A. w. Hour ETAL GAS DIODE LINEAR REGISTER Filed May 4,1956 NTS".

.rim N ...r m56 S SL *Y United States Patent c()F GAs moon LINEARREGISTER i Application May 4, 1956,;se'ria1 No. 584,4os

' z claims. (cl. S15-s45) This invention relates to step-by-stepcircuits in which changes in the state or condition of a componentcircuit stage are used to manifest a count or other control func.- Itioncorresponding to the number of applications of discrete applied pulses.ySuch circuit has utility as a register or counting device, apulsesource orcontrol circuit. The principles of the invention can beemployed to construct a linear or bar type register of the type in whichcount indicating means are successively energized and remain energized.'Y n 'It is accordingly an objectrof theA present invention to provide astep-by-step pulse-registering circuitv comprising a plurality ofcircuit stages in whichv a change of state of one stage is produced uponthe application of R.F.

energy. j p -v It is a further object of this invention to provide astepby-step circuit comprising a plurality of circuit stages which areenergized by the sequential application of R.-F. energy, according to apattern indicative of the number of pulses appli-ed to the circuit.

Other uses and ladvantages of the inventionwill become apparent uponreference to the specification and drawings in which: I

. Fig. l is a circuit schematic of one embodiment ofthe presentinvention and Fig. 2 is a representation of -a gaslled diode havingauxiliary ionizing means, which is employed as a switching diode inaccordance with the principles of this invention. l

In accordance with the principles of this invention oonduction of anindicator-storage gas diode having a suitable diiierential betweenstriking and maintaining portentials is initiated by the application ofan R.F. oscillai tory signal to an associated switching diode. rfheswitching diode is a gaseous diode placed in a switchable R.-F. eldwhich is strong enough to produce ionization'of the tube. The storageand switching diodes-are arranged according to a circuit pattern suchthat conduction ofvone l indicator-storage diode permits' energizationof a subsequent indicator-storage diode. Each of the energizedindicator-storage diodes may be left energized as the counting proceedsto form a linear or bar type register. In

known gaseous tube step-by-step circuits, conduction of a stage readiesa subsequent stage for conduction upon application of the next pulse tobe counted. The subsequent s-tage, in other words, is biased to athreshold condition and the occurrence of a spurious signal could act totrigger inadvertently the stage and register la count.

In accordance with the principles of the lpresent inveniton, astate-change of any stage requires the application ofA an ionizingpotential of considerable amplitude which is initiated by the pulse tobe counted. The system is therefore less easily atected by extraneoussignals.

Fig. 1 shows the principles of invention embodied in la linear or bartype register having a plurality of stages. An indicator-storage deviceM in each stage, which may be in the form of a gas-filled diode, issuccessively energized Vand remains energized asl thev count proceeds.Each stage of the register also includes a switch- '2,895,077 PatentedJuly 14, 1959 2 ingdiode S in the form of a gas-filled diode havingauxiliary ionizing means which is R.F. energizable.

A typical switching diode of the type employed in the present inventionis shown in Fig. 2. One embodiment of the'switching diode S comprises aconventional NE-Z type tube to which a sleeve E of conducting materialis applied. An electrode connector Ea is soldered or suitably connectedto the sleeve `as shown. Alternately, a sheath of conducting foil, or aiilm of conducting material may be deposited on the surface of the tubein a known manner. Such construction permits the application of an R.F.field to the gas diode which is strong enough to ionize the diode.

Fig. 1 shows three complete stages labeled n-|-'1, n-i-Z, and n{-3 of amultistage step-by-step circuit constructed in accordance with theprinciples of the present invention. It is'to be understood that as manysubsequent stages as desired may be constructed by merely supplementingthe circuit embodiment shown in Fig. 1 with additional stages. Theconnections yfor the preceding stage (n) yand subsequent (1H-4) stageare indicated.

`Considering the n+1 stage for example, there is shown aswitching diodelabeled SMH) which is an NE-Z type diode incorporating an auxiliarysleeve E vas described in connection with Fig. 2. One electrode of theswitching diode SMH) has a terminal `for receiving the output of theindicating diode Mn comprising part of the preceding stage n, the otherelectrode of the switching diode SMH) is coupled to the junction betweentwo resistors R1 and R2, respectively. The remaining terminal of theresistor R2 is connected to ground as indicated, while the oppositeterminal of resistor R1 which is employed as a current limiting resistorfor the indicator diode is connected to one electrode of the indicatordiode MM+ 1) of stage n+1 and to the` input electrode of the switchingdiode SMH) for the subsequent stage n-i-Z of the circuit. By connectingthe output electrode of the switching diode S to the junction of theresistors R1 and R2 in this` manner, there is no low-impedance pathpossible through Iany diode regardless of the state of conduction of anyof the diodes.

As is apparent in Fig. l, adjacent stages of the step-bystep circuit areconnected to biasing potentials of opposite polarity. That is, oneelectrode of each alternate stage indicator diode such as Mn and MMH) isconnected to a positive potential source designated as plus 140 volts inFig. 1 while one electrode in each intermediate alternate stage such asthe indicator diodes MMH) and MMH) is connected to Ia source of negativepotential designated as minus 140 volts in the drawing. The amplitude ofthe biasing voltage is under the striking potential of theindicator-storage diode by an `amount somewhat less than the minimumoutput voltage obtainable from the particular tube type used. The outputsignal comprises the diierence between the bias potential and the tubemaintaining potential. A suitable M diode is the Hivac XC-l4 or XC-17which has a nominal minimum striking potential of 145 volts and anominal maintaining potential of 75 volts.

Similarly, separate means are provided for applying an R.F. signal tothe sleeves E of adjacent switching diodeS. That is, the sleeve E foreach alternate stage such as stages n+1 and n-l-B are connected toconductor 1 3 vention, attention is directed to a pamphlet entitled,Symbolic Logic, Binary Calculation, and SC-PACS by Robert W. Brookspublished by Computer Control Company, Incorporated, Wesley, Mass.

The-output of an VR'.F. oscillator 4 comprises (inem-- put to each oftheAnd-gates 5 and'6. A'multivibrator 3 of conventional construction isemployed vto provide gating V'signals of opposite phase respectively asa second input to each of the And-gates 5 and 6. That is, the gating`signal applied by multivibrator 3 to the Andgat'e 5 will occuralternately in time sequence with respect to the' gating signal appliedby multivibrator 3 to the vAnd-gate V6. Accordingly, each of theAnd-gates 5 and 6 will act essentially as a switching deviceforalternately 'energizing the lines V1 and 2. In thisrnanner the alternateswitching diodes SMH), 80H3) etc. which for convenience are labeled inFig. l as the upper leve switching diodes are Veach influenced by theRfF. signal in alternate time sequence to the switching diodes SMH),SMH), etc. in the designated lower level. `By-'p'ass capacitors C1 andC2 are provided connecting each signal electrode of the switching diodesS to ground.

For purposes of illustration, the indicator diodes M may have'a strikingpotential of 150 volts and-a maintaining potential of 75 volts. Assumingfirst that all the M diodes are off, then all the signal electrodeterminals of the vM diodes will be at zero volts and no current will owthrough the 'switching diodes S. This condition represents the state ofall the M diodes beyond the one immediately following the last energizedM diode. 'AS- sume that one of the previous stage diodes, Mn, has beenenergized. Then signal electrode terminal of diode Mn in vstage n will-be at 140-75 which equals +65 volts. If the application of a pulseinput to multivibrator 3 has resulted in the R.F line 1 being energized,switching diode 80H1) of `stage n-l-l will berendered conducting by theapplication of an R.F. ionizing bias thereto by means of the sleeve E.The potential at electrode terminal Pn will be transmitted to electrodePMM) of stage n-l-l through the switching diode SMH) and the resistorRl. The resulting voltages established across the indicating diode M(+1will therefore be approximately +65-(l40) :205 volts. Thestorageindicator diode MMM) will therefore conduct and the voltage atthe electrode terminal P(+1) will immediately drop to 75-l40=-65 volts,changing the potential across `the referred-to switching diode 80H1) to+6'5-'(-65)=l30 volts. Whether the reduction in potential across thediode 80H1) is sulcient to extinguish such switching diode isimmaterial. Even should such switching tube remain on followingenergization of the R.F. line 1 there is no deleterious eiect other thanthe added load to the bias power supply. R.-F. line 1 need be energizedfor an interval sufficient only to insure that storage-diode M(+1) hasassumed the conducting state, but may remain energized until the nextinput pulse is applied.

Recalling that the R.-F. line 2 is not energized, then the switchingtube SMH) of the subsequent n-l-Z stage is nonconducting and nothingfurther occurs, the circuit remains in the 'stable condition describedabove and one count has been added to the register. The application of asecond pulse to be counted to the multivibrator 3` results in theenergization of R.F. line 2 and the application of an R.F. field throughthe sleeves E to each of thelower-level switching tubes Smm, SMH) etc.The R.F. field is strong enough to ionize the gas in these tubes andrender them conducting. Under such conditions of operation, thelower-level switching diode S(+2) transmits the -65 volt potentialexisting at signal electrode terminal PMM) to signal electrode terminalsPWM) of indicator diode MOH@ in the subsequent n-l-Z stage. Accordinglya voltage of 205 volts is established across the indicating diode M(+2)in a manner similar to that described in connection with the diodeMwrn-and the lindicator diode M(+2) of the subsequent n-I-Z stage isthereby energized.

In this manner as the R.F. lines 1 and 2 are alternately excited insequence consonant with each applied pulse, each stage of thestep-by-step circuit is energized or subject to a stage change insuccession.

Resetting is accomplished by lowering the bias potential onthe-indicator-storage diode M. For this purpose arnormallyl open switchSW may be employed for connecting the bias terminals to ground through aresistor R4 as Vindicated in Fig. l. A similar resetting switchisprovided vin the negative bias supply as shown on dotted lines inFig.V 1.

In order to insure uniformity of count-registration, it is necessarythat the rst-stage indicator-storage diode such as diode Mn be in aconducting state before a counting sequence begins. For this purpose,the input electrode dof the switching diode vin the iirst stage Y(Le.the `Sn istatediode) preceding storage-diode Mn is con- 'nected 'toYaibiais potential which may be derived from the V,negative Volt) biassource through a voltage divider R3, as indicated in Fig. 1. Theamplitude of such bias potential is'approximately -65 volts and ineffect simulates the output level of an indicator-storage diode,:enabling thefunctioning kof the circuit in the described manner.

The storage-indicator `diodes M according to the `invention "asVdescribed are 'integral components of each circuit stage. That is, inaddition to their indicating fanclisforag'eior memory-functions, thestate or condition of energizationiof each stage is determined by thecorresponding state or condition of each such diode. The signalsl'available at the terminals Pn, POHD etc., can therefore'beused asapulse sourceor to perform a control function.

`It Ywill be lapparent that the embodiments shown are only exemplary andthat various ymodifications can be made within the vscope of inventionfas dened in the appended'claims.

What is claimed is:

l. A step-'by-step pulse counting circuit comprising a plurality of likesta'gesconnected in cascade, each stage having Aan venergizableindicator-storage means and voltage switching means, said indicatormeans comprising `a gaseous diode, said switching means comprising agaseous diode and Aauxiliary means for applying an yRf". field thereto,Agrounded'biasing potential sources of opposite polarity, lone electrodeof the indicator -diode in adjacent stages being connected respectivelyto said grounded biasing potential sources, each of said biasingpotentials having an amplitude vless than the striking potential andgreater than the maintaining Apotential of said indicator-storagediodes, the other of said indicatordiode lelectrodes 'being directlyconnected to a first electrode of the switching diode in the adjacentsubsequent stage, Aa viifrst current limiting Vresistor connecting thesecond electrode of said swiching diode in each stage to said notherVelectrode of the indicator-diode in the same stage, a lsecond resistorconnecting said second elect-rode of sad Vswitching diode y'to groundpotential, separate vene/rgizable R.F. means *connected respectively tothe auxiliary R;'F. 'applying means of a switching diode in adjacentstages for applying an R.F, energy potential thereto, an inp'tffrapplying pulses to be counted and means connected to Ysaid input andresponsive to the pulses to be counted yfor alternately energizing eachof said energizable R.-F. means in sequence 'consonant Ywith thesequence of application of said pulses.

2. The invention of claim 1 in which the means for energizing reach ofsaid R.-F. means in sequence comprises an loscillator `and yswitchingmeans responsive to the '.pulses to be counted for connecting theoscillator to each f said R.F. means in sequence, said switching 5 i Y 6means comprising a bistable device adapted to be ener- References Citedin the tile of this patent gized to alternate states of conduction bysaid applied UNITED STATES PATENTS pulses, an And-gate connected to eachof said energizable R.F. means and means connecting opposite outputs ofiga; 1g said bistable device to each of said And-gates, respec- 52730655 Geisler Jan '1o' 1956 tively.

2,765,426 Faulkner Oct. 2, 1956

